If you are that concerned, it could be interesting to know. However, my suspicion is that the amount of lead contained in the chips is probably not significant to be a health hazard. Otherwise I would think problems would have arisen in the work force among workers exposed to the materials all day long. OSHA and other agencies would probably have looked into the matter. Further most of the exposure might be INSIDE the chips where lead might have been used as a filler and a security device. Make sure your kids don't put the chips in their mouths. And that they wash their hands after playing with them. That would probably be wise anyways considering the condition of old chips and the numbers of people touching them and where their hands might have been and so on. Unless you thouroughly wash your chips anyways.

Unless the chips are crushed up exposing the inner materials to to the outside I wouldn't, personally, be too concerned. You could also put the chips into AirTites to keep them safer also. I do that with all my chips anyways.